CEP1 — Asparagus officinalis

Summary

A4U43_C04F20260, designated CEP1 (also known as AoCEP1), encodes a cysteine proteinase of the papain-like family (Peptidase_C1A). The enzyme possesses thiol endopeptidase activity, cysteine-type peptidase activity, and protein homodimerization activity, and is annotated to proteinase-activated receptor binding. CEP1 is associated with proteolysis and nitric oxide storage, and localizes to the vacuole, protein storage vacuole, lysosome, aleurone body, cytoplasmic vesicle, and ER lumen. Studies of related genes in other species link the CEP1 family to cysteine-type endopeptidase activity (EC 3.4.22.-) and to proteins such as pollen allergen Amb a 11, vignain, and mucunain, though these associations are not established for asparagus.